1. Field of the Invention
An embodiment of the present invention generally relates semiconductor devices, and more specifically to a pillar type capacitor of a semiconductor device and a method for forming the same.
2. Description of the Related Art
Due to rapid development of the process technology of small-sized semiconductors, high-integration of memory products has is been accelerated to reduce the unit cell area and lower the operating voltage. However, the charging capacity required in the operation of memory devices has been continuously required to be over 25 fF/cell in order to prevent generation of soft errors and shortening of the refresh time.
In order to secure the charging capacity required in the next generation DRAM products, MIM-type capacitors adopting a high-k dielectric film have been developed.
In DRAM products adopting a fine metal line process of 50 nm˜60 nm, in order to obtain the cell capacitance of over 25 fF/cell, the structure of the storage node is changed from a concave shape into a cylinder shape, thereby obtaining a larger charging capacitance.
However, it is difficult to use the cylinder-type storage node structure in giga DRAM products having a fine metal line width of less than 50 nm because a space where a capacitor can be formed by depositing a dielectric film of about 100 Å and a plate node of about 200 Å is not sufficiently provided in a cell region while securing a space of over 25 nm (250 Å) for insulation between the adjacent storage nodes.